Spinners in a multibar don't spin while a child process runs

[migerh]

I observed that spinners do not spin while a child process runs that was spawned with std::process::Command. Especially when they are in a multibar. I created a small example that shows the issue: https://github.com/migerh/indicatif-multibar

The use_multibar_with_timeout_for_finish() example shows that while the child process is running, the spinners in the multibar do not update. They start spinning as soon as the child process finishes, though.

[andreivasiliu]

The confusion here comes from the fact that calling .join() must be done in a separate thread, as that is what is doing the rendering. Same as #77.

#33 would have prevented this.

[mitsuhiko]

Going to close this as duplicate of #33.